The network-reference extension to PlanNetPractitionerRole species a cardinality of `0..1`.  The net effect of this is to require one PractitionerRole per insurance network. This probably makes some sense for the original use case of Payer provider directories, where the search was primarily intended to find providers that are in network.  However, in other directory use cases the PractitionerRole has a lot of valuable information beyond the basics. – e.g. contact information, periods during which the practitioner is at that location, etc.

I'm asking because we have a national provider directory that attempts to follow the Plan Net IG as closely as possible.  However, our primary use case is tracking contact information and endpoints by PractitionerRole (i.e. Practitioner + Organization + Location).  We would like to add Insurance information, but because of the cardinality of `0..1` we would have to create one PractitionerRole per Network for a given provider/location.  Based on some preliminary exploration, this could end up requiring 100s of practitioner roles when tracking network participation for many insurance companies, where one would have done but for the constraint.  This presents a substantial cost in both processing and storage, and would also likely have a significant negative impact on performance for queries like, `show me all the insurance networks Doctor X participates in`.

Is there some hidden logic to this having a cardinality of 1 for this that I'm not seeing?  Is there any possibility that a future version of PlanNet could allow more than one instance of this extension for a given PractitionerRole?